From 510aaf6d528210c5e8a6159f9b80b32615e88c5f Mon Sep 17 00:00:00 2001 From: Hans Dedecker Date: Thu, 11 Jan 2018 16:31:57 +0100 Subject: [PATCH 1/1] odhcp6c: add -x opt:val support Add -x opt:val command support which allows to add options in sent packets. The opt argument can be either specified as a string for well known options, a decimal or a base-16 encoded value. For some well-known options val will be parsed according to the data format specified in the corresponding RFCs. Supported well-know options are : authentication (option 11) : stream of base-16 encoded bytes userclass (option 15) : array of strings vendorclass (option 16) : stream of base-16 encoded bytes dns (option 23) : array of IPv6 addresses search (option 24) : Domain name sntpservers (option 31) : array of IPv6 addresses ntpserver (option 56) : stream of base-16 encoded bytes sipserver_d (option 21) : Domain name sipserver_a (option 22) : array of IPv6 addresses The val array elements can be separated by either a white space, comma or tab. The val for non well-known options is a stream of base-16 encoded bytes. Config examples : -x sntpservers:3001:3001::1,3001:3001::2 -x 11:00000000000000000000006674692F -x 0x3e8:ABCDEF Signed-off-by: Hans Dedecker --- src/dhcpv6.c | 6 + src/odhcp6c.c | 361 +++++++++++++++++++++++++++++++++++++++++++++++++- src/odhcp6c.h | 19 +++ 3 files changed, 381 insertions(+), 5 deletions(-) diff --git a/src/dhcpv6.c b/src/dhcpv6.c index 6f61560..a905d5b 100644 --- a/src/dhcpv6.c +++ b/src/dhcpv6.c @@ -225,6 +225,7 @@ enum { IOV_VENDOR_CLASS, IOV_USER_CLASS_HDR, IOV_USER_CLASS, + IOV_OPTS, IOV_RECONF_ACCEPT, IOV_FQDN, IOV_HDR_IA_NA, @@ -426,6 +427,10 @@ static void dhcpv6_send(enum dhcpv6_msg type, uint8_t trid[3], uint32_t ecs) // Request Information Refresh uint16_t oro_refresh = htons(DHCPV6_OPT_INFO_REFRESH); + // Option list + size_t opts_len; + void *opts = odhcp6c_get_state(STATE_OPTS, &opts_len); + // Build vendor-class option size_t vendor_class_len, user_class_len; struct dhcpv6_vendorclass *vendor_class = odhcp6c_get_state(STATE_VENDORCLASS, &vendor_class_len); @@ -469,6 +474,7 @@ static void dhcpv6_send(enum dhcpv6_msg type, uint8_t trid[3], uint32_t ecs) [IOV_VENDOR_CLASS] = {vendor_class, vendor_class_len}, [IOV_USER_CLASS_HDR] = {&user_class_hdr, user_class_len ? sizeof(user_class_hdr) : 0}, [IOV_USER_CLASS] = {user_class, user_class_len}, + [IOV_OPTS] = { opts, opts_len }, [IOV_RECONF_ACCEPT] = {&reconf_accept, sizeof(reconf_accept)}, [IOV_FQDN] = {&fqdn, fqdn_len}, [IOV_HDR_IA_NA] = {&hdr_ia_na, sizeof(hdr_ia_na)}, diff --git a/src/odhcp6c.c b/src/odhcp6c.c index dfcdf5e..db6fe2e 100644 --- a/src/odhcp6c.c +++ b/src/odhcp6c.c @@ -17,6 +17,8 @@ #include #include #include +#include +#include #include #include #include @@ -40,9 +42,15 @@ ((((__const uint32_t *) (a))[0] & htonl (0xfe000000)) \ == htonl (0xfc000000)) #endif +#define ARRAY_SEP " ,\t" static void sighandler(int signal); static int usage(void); +static int add_opt(const uint16_t code, const uint8_t *data, + const uint16_t len); +static int parse_opt_data(const char *data, uint8_t **dst, + const unsigned int type, const bool array); +static int parse_opt(const char *opt); static uint8_t *state_data[_STATE_MAX] = {NULL}; static size_t state_len[_STATE_MAX] = {0}; @@ -60,6 +68,53 @@ static char *ifname = NULL; static unsigned int script_sync_delay = 10; static unsigned int script_accu_delay = 1; +static struct odhcp6c_opt opts[] = { + { .code = DHCPV6_OPT_CLIENTID, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_SERVERID, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_IA_NA, .flags = OPT_INTERNAL, .str= NULL }, + { .code = DHCPV6_OPT_IA_TA, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_IA_ADDR, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_ORO, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_PREF, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_ELAPSED, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_RELAY_MSG, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_AUTH, .flags = OPT_U8, .str = "authentication" }, + { .code = DHCPV6_OPT_UNICAST, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_STATUS, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_RAPID_COMMIT, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_USER_CLASS, .flags = OPT_USER_CLASS | OPT_ARRAY, .str = "userclass" }, + { .code = DHCPV6_OPT_VENDOR_CLASS, .flags = OPT_U8, .str = "vendorclass" }, + { .code = DHCPV6_OPT_INTERFACE_ID, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_RECONF_MESSAGE, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_RECONF_ACCEPT, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_RECONF_ACCEPT, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_DNS_SERVERS, .flags = OPT_IP6 | OPT_ARRAY, .str = "dns" }, + { .code = DHCPV6_OPT_DNS_DOMAIN, .flags = OPT_DNS_STR, .str = "search" }, + { .code = DHCPV6_OPT_IA_PD, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_IA_PREFIX, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_SNTP_SERVERS, .flags = OPT_IP6 | OPT_ARRAY, .str = "sntpservers" }, + { .code = DHCPV6_OPT_INFO_REFRESH, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_NTP_SERVER, .flags = OPT_U8, .str = "ntpserver" }, + { .code = DHCPV6_OPT_SIP_SERVER_D, .flags = OPT_DNS_STR, .str = "sipserver_d" }, + { .code = DHCPV6_OPT_SIP_SERVER_A, .flags = OPT_IP6 | OPT_ARRAY, .str = "sipserver_a" }, + { .code = DHCPV6_OPT_AFTR_NAME, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_PD_EXCLUDE, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_SOL_MAX_RT, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_INF_MAX_RT, .flags = OPT_INTERNAL, .str = NULL }, +#ifdef EXT_CER_ID + { .code = DHCPV6_OPT_CER_ID, .flags = OPT_INTERNAL, .str = NULL }, +#endif + { .code = DHCPV6_OPT_S46_RULE, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_S46_BR, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_S46_DMR, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_S46_V4V6BIND, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_S46_PORTPARAMS, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_S46_CONT_MAPE, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_S46_CONT_MAPT, .flags = OPT_INTERNAL, .str = NULL }, + { .code = DHCPV6_OPT_S46_CONT_LW, .flags = OPT_INTERNAL, .str = NULL }, + { .code = 0, .flags = 0, .str = NULL }, +}; + int main(_unused int argc, char* const argv[]) { static struct in6_addr ifid = IN6ADDR_ANY_INIT; @@ -78,12 +133,12 @@ int main(_unused int argc, char* const argv[]) int verbosity = 0; bool help = false, daemonize = false; int logopt = LOG_PID; - int c; + int c, res; unsigned int client_options = DHCPV6_CLIENT_FQDN | DHCPV6_ACCEPT_RECONFIGURE; unsigned int ra_options = RA_RDNSS_DEFAULT_LIFETIME; unsigned int ra_holdoff_interval = RA_MIN_ADV_INTERVAL; - while ((c = getopt(argc, argv, "S::N:V:P:FB:c:i:r:Ru:s:kt:m:Lhedp:fav")) != -1) { + while ((c = getopt(argc, argv, "S::N:V:P:FB:c:i:r:Ru:x:s:kt:m:Lhedp:fav")) != -1) { switch (c) { case 'S': allow_slaac_only = (optarg) ? atoi(optarg) : -1; @@ -241,6 +296,16 @@ int main(_unused int argc, char* const argv[]) ++verbosity; break; + case 'x': + res = parse_opt(optarg); + if (res) { + if (res > 0) + return res; + + help = true; + } + break; + default: help = true; break; @@ -321,7 +386,7 @@ int main(_unused int argc, char* const argv[]) continue; do { - int res = dhcpv6_request(mode == DHCPV6_STATELESS ? + res = dhcpv6_request(mode == DHCPV6_STATELESS ? DHCPV6_MSG_INFO_REQ : DHCPV6_MSG_REQUEST); bool signalled = odhcp6c_signal_process(); @@ -347,7 +412,7 @@ int main(_unused int argc, char* const argv[]) signal_usr1 = false; script_call("informed", script_sync_delay, true); - int res = dhcpv6_poll_reconfigure(); + res = dhcpv6_poll_reconfigure(); odhcp6c_signal_process(); if (res > 0) @@ -379,7 +444,7 @@ int main(_unused int argc, char* const argv[]) while (!signal_usr2 && !signal_term) { // Renew Cycle // Wait for T1 to expire or until we get a reconfigure - int res = dhcpv6_poll_reconfigure(); + res = dhcpv6_poll_reconfigure(); odhcp6c_signal_process(); if (res > 0) { script_call("updated", 0, false); @@ -462,6 +527,11 @@ static int usage(void) " -F Force IPv6-Prefix\n" " -V Set vendor-class option (base-16 encoded)\n" " -u Set user-class option string\n" + " -x : Add option opt (with value val) in sent packets (cumulative)\n" + " Examples of IPv6 address, string and base-16 encoded options:\n" + " -x dns:2001:2001::1,2001:2001::2 - option 23\n" + " -x 15:office - option 15 (userclass)\n" + " -x 0x1f4:ABBA - option 500\n" " -c Override client-ID (base-16 encoded 16-bit type + value)\n" " -i Use a custom interface identifier for RA handling\n" " -r Options to be requested (comma-separated)\n" @@ -685,6 +755,20 @@ static void odhcp6c_expire_list(enum odhcp6c_state state, uint32_t elapsed) } } +static uint8_t *odhcp6c_state_find_opt(const uint16_t code) +{ + size_t opts_len; + uint8_t *odata, *opts = odhcp6c_get_state(STATE_OPTS, &opts_len); + uint16_t otype, olen; + + dhcpv6_for_each_option(opts, &opts[opts_len], otype, olen, odata) { + if (otype == code) + return &odata[-4]; + } + + return NULL; +} + void odhcp6c_expire(void) { time_t now = odhcp6c_get_milli_time() / 1000; @@ -778,3 +862,270 @@ static void sighandler(int signal) else signal_term = true; } + +static int add_opt(const uint16_t code, const uint8_t *data, const uint16_t len) +{ + struct { + uint16_t code; + uint16_t len; + } opt_hdr = { htons(code), htons(len) }; + + if (odhcp6c_state_find_opt(code)) + return -1; + + if (odhcp6c_add_state(STATE_OPTS, &opt_hdr, sizeof(opt_hdr)) || + odhcp6c_add_state(STATE_OPTS, data, len)) { + syslog(LOG_ERR, "Failed to add option %hu", code); + return 1; + } + + return 0; +} + +struct odhcp6c_opt *odhcp6c_find_opt(const uint16_t code) +{ + struct odhcp6c_opt *opt = opts; + + while (opt->code) { + if (opt->code == code) + return opt; + + opt++; + } + + return NULL; +} + +static struct odhcp6c_opt *odhcp6c_find_opt_by_name(const char *name) +{ + struct odhcp6c_opt *opt = opts; + + if (!name || !strlen(name)) + return NULL; + + while (opt->code && (!opt->str || strcmp(opt->str, name))) + opt++; + + return (opt->code > 0 ? opt : NULL); +} + +/* Find first occurrence of any character in the string + * within the string + * */ +static char *get_sep_pos(const char *haystack, const char *needles) +{ + unsigned int i; + char *first = NULL; + + for (i = 0; i < strlen(needles); i++) { + char *found = strchr(haystack, needles[i]); + if (found && ((found < first) || (first == NULL))) + first = found; + } + + return first; +} + +static int parse_opt_u8(const char *src, uint8_t **dst) +{ + int len = strlen(src); + + *dst = realloc(*dst, len/2); + if (!*dst) + return -1; + + return script_unhexlify(*dst, len, src); +} + +static int parse_opt_dns_string(const char *src, uint8_t **dst, const bool array) +{ + int i_len = strlen(src); + int o_len = 0; + char *sep = get_sep_pos(src, ARRAY_SEP); + + if (sep && !array) + return -1; + + do { + uint8_t tmp[256]; + + if (sep) { + *sep = 0; + sep++; + } + + int len = dn_comp(src, tmp, sizeof(tmp), NULL, NULL); + if (len < 0) + return -1; + + *dst = realloc(*dst, o_len + len); + if (!*dst) + return -1; + + memcpy(&((*dst)[o_len]), tmp, len); + + o_len += len; + i_len -= strlen(src) + (sep ? 1 : 0); + src = sep; + + if (src) + sep = get_sep_pos(src, ARRAY_SEP); + } while (i_len); + + return o_len; +} + +static int parse_opt_ip6(const char *src, uint8_t **dst, const bool array) +{ + int i_len = strlen(src); + int o_len = 0; + char *sep = get_sep_pos(src, ARRAY_SEP); + + if (sep && !array) + return -1; + + do { + int len = sizeof(struct in6_addr); + + if (sep) { + *sep = 0; + sep++; + } + + *dst = realloc(*dst, o_len + len); + if (!*dst) + return -1; + + if (inet_pton(AF_INET6, src, &((*dst)[o_len])) < 1) + return -1; + + o_len += len; + i_len -= strlen(src) + (sep ? 1 : 0); + src = sep; + + if (src) + sep = get_sep_pos(src, ARRAY_SEP); + } while (i_len); + + return o_len; +} + +static int parse_opt_user_class(const char *src, uint8_t **dst, const bool array) +{ + int i_len = strlen(src); + int o_len = 0; + char *sep = get_sep_pos(src, ARRAY_SEP); + + if (sep && !array) + return -1; + + do { + if (sep) { + *sep = 0; + sep++; + } + uint16_t str_len = strlen(src); + + *dst = realloc(*dst, o_len + str_len + 2); + if (!*dst) + return -1; + + struct user_class { + uint16_t len; + uint8_t data[]; + } *e = (struct user_class *)&((*dst)[o_len]); + + e->len = ntohs(str_len); + memcpy(e->data, src, str_len); + + o_len += str_len + 2; + i_len -= str_len + (sep ? 1 : 0); + src = sep; + + if (src) + sep = get_sep_pos(src, ARRAY_SEP); + } while (i_len); + + return o_len; +} + +static int parse_opt_data(const char *data, uint8_t **dst, const unsigned int type, + const bool array) +{ + int ret = 0; + + switch (type) { + case OPT_U8: + ret = parse_opt_u8(data, dst); + break; + + case OPT_DNS_STR: + ret = parse_opt_dns_string(data, dst, array); + break; + + case OPT_IP6: + ret = parse_opt_ip6(data, dst, array); + break; + + case OPT_USER_CLASS: + ret = parse_opt_user_class(data, dst,array); + break; + + default: + ret = -1; + break; + } + + return ret; +} + +static int parse_opt(const char *opt) +{ + uint32_t optn; + char *data; + uint8_t *payload = NULL; + int payload_len; + unsigned int type = OPT_U8; + bool array = false; + struct odhcp6c_opt *dopt = NULL; + int ret = -1; + + data = get_sep_pos(opt, ":"); + if (!data) + return -1; + + *data = '\0'; + data++; + + if (strlen(opt) == 0 || strlen(data) == 0) + return -1; + + dopt = odhcp6c_find_opt_by_name(opt); + if (!dopt) { + char *e; + optn = strtoul(opt, &e, 0); + if (*e || e == opt || optn > USHRT_MAX) + return -1; + + dopt = odhcp6c_find_opt(optn); + } else + optn = dopt->code; + + /* Check if the type for the content is well-known */ + if (dopt) { + /* Refuse internal options */ + if (dopt->flags & OPT_INTERNAL) + return -1; + + type = dopt->flags & OPT_MASK_SIZE; + array = ((dopt->flags & OPT_ARRAY) == OPT_ARRAY) ? true : false; + } + + payload_len = parse_opt_data(data, &payload, type, array); + if (payload_len > 0) + ret = add_opt(optn, payload, payload_len); + + free(payload); + + return ret; +} diff --git a/src/odhcp6c.h b/src/odhcp6c.h index f17b43d..d92b6bc 100644 --- a/src/odhcp6c.h +++ b/src/odhcp6c.h @@ -51,6 +51,7 @@ enum dhcvp6_opt { DHCPV6_OPT_RAPID_COMMIT = 14, DHCPV6_OPT_USER_CLASS = 15, DHCPV6_OPT_VENDOR_CLASS = 16, + DHCPV6_OPT_INTERFACE_ID = 18, DHCPV6_OPT_RECONF_MESSAGE = 19, DHCPV6_OPT_RECONF_ACCEPT = 20, DHCPV6_OPT_DNS_SERVERS = 23, @@ -262,6 +263,7 @@ enum odhcp6c_state { STATE_AFTR_NAME, STATE_VENDORCLASS, STATE_USERCLASS, + STATE_OPTS, STATE_CER, STATE_S46_MAPT, STATE_S46_MAPE, @@ -322,6 +324,22 @@ struct odhcp6c_request_prefix { uint16_t length; }; +enum odhcp6c_opt_flags { + OPT_U8 = 0, + OPT_IP6, + OPT_DNS_STR, + OPT_USER_CLASS, + OPT_MASK_SIZE = 0x0F, + OPT_ARRAY = 0x10, + OPT_INTERNAL = 0x20, +}; + +struct odhcp6c_opt { + uint16_t code; + uint8_t flags; + const char *str; +}; + int init_dhcpv6(const char *ifname, unsigned int client_options, int sol_timeout); int dhcpv6_set_ia_mode(enum odhcp6c_ia_mode na, enum odhcp6c_ia_mode pd); int dhcpv6_request(enum dhcpv6_msg type); @@ -362,3 +380,4 @@ bool odhcp6c_update_entry(enum odhcp6c_state state, struct odhcp6c_entry *new, void odhcp6c_expire(void); uint32_t odhcp6c_elapsed(void); +struct odhcp6c_opt *odhcp6c_find_opt(const uint16_t code); -- 2.30.2